What does "test reliability" refer to in assessments?

Test reliability refers to the consistency of what the assessment measures. This concept is crucial in educational and psychological testing because it ensures that the results are stable and dependable across different instances of the assessment. In essence, if a test is reliable, repeated applications of the assessment under similar conditions will yield similar scores, indicating that the measure is consistently capturing the intended construct.

For example, if a student takes a math test today and then takes the same test after a week and scores similarly, the test can be considered reliable. Reliability can manifest in various forms, such as internal consistency (how well the items on a test measure the same construct) and test-retest reliability (how consistent results are when the same test is administered at two different times).

The other choices do not accurately define "test reliability." Fairness relates more to equity and impartiality in the assessment process. Speed of completion pertains to the duration taken to finish a test, which does not affect its reliability. Subjective interpretation deals with how results can be individually perceived, which can vary and create inconsistencies, thereby separating it from the concept of reliability.